Two inmates are suing the ­Minnesota Department of Corrections seeking access to costly drug treatments for hepatitis C, a serious liver condition that in many cases can be cured with a new generation of medications.

Filed in federal court this month, the lawsuit taps into a national debate over how prison systems can afford the costly new drugs, some of which carry a sticker price of $1,000 per pill and $90,000 for the full treatment.

In a written statement, the Corrections Department said that it could not comment on the lawsuit, but added: "It is not true that offenders do not have access to the new ­medications."

The lawsuit was filed May 1 on behalf of two inmates by a St. Paul group called the International Humanitarian Law Institute.

Breakthrough medicine for hepatitis C started being approved in the United States in late 2013, the lawsuit states, and has become the standard of care with a 95 percent cure rate. Yet the inmates have been denied access "in deliberate indifference to their serious medical needs," the lawsuit states.

Peter Erlinder, the institute's ­director, cited state figures that suggest at least 1,350 inmates at state facilities have tested positive, or will test positive, for hepatitis C. The lawsuit seeks class-action status.

"For nonmedical reasons, defendants refuse to provide the 'breakthrough' drug treatment … which will cure plaintiffs' [hepatitis C] infection," the lawsuit states.

Hepatitis C affects somewhere between 2.3 million and 5.2 million people in the United States. Many who are infected with the virus lack symptoms, but the disease at its worst can lead to scarring of the liver, liver cancer and liver failure.

The advent of new drug treatments has caused financial stress for public and ­private health insurers.

Minnesota's Medicaid program paid pharmacies about $1 million for hepatitis C drugs in 2013 — a tab that jumped to more than $9 million last year. The new drugs had a similar effect on the federal Medicare program, which saw spending on medicine for hepatitis C jump from $286 million in 2013 to $4.5 billion last year.

Drug companies have defended the cost of new medications because they offer a cure to so many patients. Plus, successful treatment can avoid significant costs, such as liver transplants that can generate $500,000 in long-term treatment costs. There's growing evidence that treatment with the drugs is cost-effective for certain patients, experts say.

But in the near term, the treatment costs threaten to overwhelm health care budgets in prisons, where inmates are at greater risk of infection than the general population, said Dr. Brian Montague, an assistant professor of medicine at Brown University.

Some commercial health insurers are controlling costs by limiting access to only certain patients in advanced stages of liver disease. Yet even with such policies in place, the Rhode Island prison health care system would see a fivefold increase in its pharmacy budget, Montague and colleagues wrote in a study published earlier this year.

"With immense costs projected with new treatment, it is unlikely that correctional facilities will have the capacity to treat all those afflicted," they wrote in the April 1 edition of the Journal of Urban Health.

Twitter: @chrissnowbeck